The water misting fan is a device for providing personal and environmental cooling by spraying atomized water droplets into an air stream. The droplets evaporate thereby drawing heat out of the surrounding air. Non-evaporated droplets impinge on the user and further evaporation draws heat out of clothing and skin of the user or surrounding surfaces. These are sometimes called “swamp coolers”. For the benefit of the cooling, the cost is increased humidity, which can decrease comfort. Swamp coolers work poorly in confined or very humid environments and are more suited to hot, but low humidity, environments like the desert.
The utility of the device is improved by increasing the amount of water evaporated in the air stream as opposed to wetting the user and then trying to evaporate water off the skin and clothing. This is achieved by increasing the air flow and/or making water droplets smaller.
Portable units usually use a manually-actuated piston pump to generate the high pressures needed for fine atomization of the water. Portable water misting fans usually incorporate DC motors with dry cell batteries for portability.
In the art there are numerous instances of coupling a sprayer nozzle with a fan to produce an improved personal or environmental cooling apparatus. In the handheld realm, the portable misting fan described in Steiner '495 is the benchmark for the battery operated misting fans where a trigger or pushbutton operated sprayer discharges a fine mist of water into the air stream. These are typically single nozzle/single blower apparatuses.
In use, the user fills the reservoir through a fill port by removing the fill cap. Here, the port is large enough to accept ice cubes to keep the water in the reservoir cool. The user squeezes the pump trigger to manually pump water from the reservoir to moderate pressures through a narrow orifice on the nozzle. The water comes out as a spray of droplets. An electric motor driven fan is located proximate to the nozzle. There is typically an enclosure that surrounds the batteries, motor and pump body. Here the fan body is supported on the sprayer which, in turn, mounts to the top of the bottle. If the nozzle is located behind the fan blades, and the fan is turned on, the droplet spray will be directed into the air stream to be directed at the user and to enhance evaporation. The fan can be operated independently of the pump so the unit can act in a fan-only capacity.
In the case of designs such as Steiner '495, the water misting fan exhibits a problem with aesthetics and durability. Durability is an important feature because these products are sold for outdoor use and at amusement parks where they don't receive tender care. Also, as with any consumer good, the aesthetics are important to achieve greater customer satisfaction and commercialization of the product.
The durability problem comes from the interface between the reservoir, sprayer and the fan enclosure. At some point, there is a coupling between the motor enclosure and sprayer (further attached to the reservoir) or motor enclosure and reservoir that ends up being a weak link. The coupling has to be undone and reattached for various purposes of changing the batteries, filling the reservoir or removing the fan for separate use. If these couplings could be removed, the water misting fan could be made much more durable.
Further, conventional water misting fans have vulnerable triggers and attachment collars where the sprayer mates with the top of the bottle. These are two areas where the end user tends to break the misting fan. As such, the fan should be evaluated for its durability by evaluating how it performs in drop testing, how it holds up when packed away in a purse or beach bag, and the strength of its attachment points like straps and belt clips.
The aesthetic problem comes from the compromises of the separable component design. In the instance of portable bottle type misting fan designs, there is an unsightly, cheap-looking screw collar that detracts from the smooth lines of the fan head. Similarly, the use of the standard sprayer requires the use of the blocky nozzle and cheap-looking trigger that detract from the overall design. The design does not allow us to hide the chunky-looking sprayer and nozzle within the enclosure because of size and functional reasons. The grip is often uncomfortable because it is too large around for smaller hands or the weight is not well balanced.
What is lacking in the prior art is a water misting fan that can withstand the rigors of outdoor use while still looking sleek and stylish. The design should also store compactly and possess a minimum of parts that can be lost. Moving or wearing parts should be kept to a minimum. The handle or grippable feature of the enclosure should be narrow enough for smaller hands to grasp and the trigger should be located conveniently to the index finger and not pinch adjacent fingers.
Further, to be economical, the design should have a minimum number of seals and as many integrated components as possible, these using economical injection molding or blow molding to render the features. For performance, it has been found that a flexible fan blade without any guard in front or back provides better air flow without compromising user safety. A guard around the periphery of the impeller improves durability. Other considerations of the misting fan design should make efficient use of the space inside the enclosure, especially to maximize reservoir volume.
Further, it has now been determined that by re-locating the battery compartment to a location removed from air flow stream created by the impeller blade, air flow is improved. This is especially realized in the variation of the portable misting fan which includes a shroud surrounding the impeller blades which serves the function of protecting the impeller blades from breakage and protects the user from possible injury from the impeller blades.
The present device re-locates the battery compartment to a separate compartment which may be positioned in the base of the shroud, or to a separate compartment which may be formed in the wall of the reservoir.
The reservoir may be formed as a separate compartment which is then surrounded by a handle portion and includes an enlarged neck portion which extends outwardly from a bottom opening in the handle portion. The lower portion of the reservoir and surrounding handle portion is enlarged which serves a two-fold purpose of improving the fluid volume of the reservoir and providing a dog-bone shaped configuration allowing for improved grippability.